The amount and variety of information that can be accessed through a computer continues to increase at an astounding rate. The Internet, in particular, has enabled computer users to access a wide variety of information from other computers located all over the world.
As computers have become more and more connected to various information sources, however, computers have become increasingly at risk for contracting computer viruses. A computer virus can generally include any malicious or otherwise surreptitious computer program that “infects” a computer and performs undesirable activities in the computer. Some computer viruses are simply mischievous in nature; however, other viruses can cause a significant amount of harm to a computer and/or its user, up to and including stealing private data, deleting data and/or causing a complete computer failure. Some viruses even permit a third party to gain control of a user's computer outside of the knowledge of the user, while others may utilize a user's computer in performing other malicious activities such as launching denial-of-service (DOS) attacks against other computers.
Viruses can take many different forms, and can be spread in a wide variety of manners, e.g., as email attachments, macros or scripts, Trojan horses, worms, logic bombs, etc. (all of which, for the purposes herein, will be referred to hereinafter as “viruses”). Often, a virus will hide, or “infect”, an otherwise healthy computer program so that the virus will be activated when the infected computer program is executed. Viruses typically also have the ability to replicate and spread to other computer programs, as well as other computers.
To address the risks associated with viruses, significant efforts have been directed toward the development of anti-virus computer programs that attempt to detect and/or remove viruses that attempt to infect a computer. Such efforts have resulted in a continuing competition where virus creators continually attempt to create increasingly sophisticated viruses and anti-virus developers continually attempt to protect computers from new viruses.
One capability of many conventional anti-virus programs is the ability to perform virus checking on virus-susceptible computer files after such files have been received and stored in a computer, e.g., after downloading emails or executable files from the Internet. Server-based anti-virus programs are also typically used to virus check the files accessible by a server. Such anti-virus programs, for example, are often used by web sites for internal purposes, particularly download sites that provide user access to a large number of downloadable executable files that are often relatively susceptible to viruses.
Virus checking is often both processor- and bandwidth-intensive, and as a result, conventional anti-virus programs are typically limited to performing virus checks for files that are stored generally in the same computers upon which such programs are executing. Thus, while specific entities, including end users and web sites, may be capable of performing virus checking on files stored locally on those entities' computers, oftentimes those entities are not capable of determining the viral risks associated with files under the control of other entities, at least not until such files can be retrieved and checked locally by an entity's anti-virus program.
The distributed and decentralized nature of the Internet and other shared computer networks, in particular, highlights the aforementioned limitations of conventional anti-virus technologies, since oftentimes a user will navigate to a wide variety of web sites and be able to download virus-susceptible files from a large number of entities outside of the control of the user.
A particular example of the risks is in performing Internet-based searches and accessing search results generated thereby. Sophisticated search engines and associated “portal” sites have been developed by search providers for the express purpose of facilitating the location of web sites, pages and other files of interest to users. Many conventional search engines, for example, maintain index- and/or directory-based computer databases that attempt to catalog content on the Internet such that relevant web pages or other files may be identified to users in response to search requests sent to the search engines by such users. Often, such databases include a large number of records associated with different files such that the records, rather than the files themselves, are searched.
Search results are typically returned to a search engine user in the form of a formatted list of entries or records that are associated with files such as web pages that match a search request. Often, hypertext links are provided so a user can access the associated files by selecting the links. Given, however, that the files are often hosted and controlled by entities other than a search provider, the search provider typically has no mechanism for determining the virus risks presented by the files identified in search results sent to users of the search engine. As a result, files accessed through search engine results often present a comparatively higher degree of risk of infection to users. Particularly if a user is not using local anti-virus software, such a user is significantly at risk of contracting a virus.
The competition between commercial search providers, whether such providers provide searching sites or search engines used by others, has become relatively tight, and as a result, search providers are continuously attempting to increase the number of users of such services, particularly those where revenue is derived principally from advertisements or subscriptions. For example, many search sites attempt to add additional functionality and features to induce additional users to use their services.
Given the stiff competition between search providers, it would be highly detrimental for a search provider to be identified even tangentially as the source of a virus that performs mischief in a user's computer. Nonetheless, given the lack of control that most search providers have over the files identified by the search results generated by such providers or their technology, often it is infeasible to create even a marginal level of trust that specific search results will not present a significant risk of infection to users.
The risks provided by Internet-based searching may also apply to other computer database searching environments, particularly where the possibility exists that files associated with certain search results will not be under the control of the entity that generates the search results. Therefore, a significant need exists in the art for a manner of decreasing the risks of viruses associated with accessing search results from computer database searches.